You will have different boarding numbers, but practically speaking, they should not be that far away from each other, such that you could wait for them (and their slightly later number) to ensure that you get good joint family pictures between the terminal and the ship (right before stepping on the ship). Never too early for them to start filling your Shutters photo folder!
I would still suggest arriving together (for your PAT), as that would give you plenty of time to get checked-in, take a picture with Captain Mickey (or Minnie) in the terminal, get kids registered at the youth desk (if applicable), etc., etc., before your boarding number is called. The extra 30 minutes will seem like no time!